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  <title>Document</title>
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  <script>
    /* let number = new Number(99)
    console.log(number + 1); */

    /* let number = 99;
    console.log(typeof number);

    let wangyang = number.toString()
    console.log(typeof wangyang); */

    let number = 99.559;
    console.log(Number.isInteger(number)); // 判断是否为正数
    console.log(number.toFixed(2)); // 保留小数点后两位
  </script>
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